1. Field of the Invention
The present invention relates to an ink jet printhead, and, more particularly, to a method and apparatus for thermal control of an ink jet printhead.
2. Description of the Related Art
In an ink jet printer, the drop and mass of the ink are dependent upon the temperature of the head. If the temperature of the head varies significantly from swath to swath, then a color shift will become visible, a phenomenon which is referred to as "banding." In order to overcome this problem, ink jet printers typically add heat to the print chips by the use of substrate heaters. It is known for a print chip of an inkjet printer to be attached to a plastic support. Such plastic supports typically do not remove heat from the print chip in an efficient manner and therefore the ability to print dense areas on the page is thermally limited.
In order to provide a better path for heat to escape to the ambient air, it is also known for print chips to be attached to a metal body or heatsink. By attaching the print chip to a metal heatsink, swings in chip temperature are reduced. However, the use of a metal heatsink significantly affects the thermal control of the print chip.
As ink jet printers begin to move into the business market, it becomes necessary to manage the printhead in a more efficient manner. The use of print chips attached to heatsinks for use in an inkjet printer requires improvements to the known print chip temperature control methods. What is needed in the art is a method of more accurately controlling the temperature of a print chip.